Ignition system controlled by a pilot relay



United States Patent Philippe Vienat Thetford Mines, Quebec, Canada 784,612

Dec. 18, 1968 Dec. 1, 1970 Louis-Philippe Duval Thetford Mines, Quebec, Canada Inventor Appl No. Filed Patented Assignee IGNITION SYSTEM CONTROLLED BY A PILOT RELAY 10 Claims, 6 Drawing Figs.

U.S. Cl 123/148, 123/149, 123/179, 315/209 Int. Cl F02p 3/02 Field of Search 123/148.

148(AC), 148(8), 148(D), 148(5), 148(DS), 149, l49(D);3l5/209 [56] References Cited UNITED STATES PATENTS 1,258,785 3/1918 Kettering et al. 123/148DS 3,452,731 7/1969 Becker 123/148DS Primary Examiner-Laurence M Goodridge AttorneyPierre Lesperance ABSTRACT: An improved ignition system having a vibrator to produce series of auxiliary sparks, wherein a pilot relay is used to control the timing of the sparks at the spark plugs, such that closure of the breaker points will open the vibrator circuit, and upon subsequent opening of the breaker points, the first spark will always be produced by the latter, not by the vibrator.

Patehted Dec. 1, 1970 Sheet 1 of 2 INVENTOR Philippe V/ENAT BY W AGENT Patented Dec. 1, 1970 Sheet m N WE V we w m IGNITION SYSTEM (IONTROLLED BY A PILOT RELAY The present invention relates to an ignition system for internal combustion engines and more particularly, to an ignition system having a vibrator to produce auxiliary sparks.

It has been discovered that an ignition system using a vibrator to produce auxiliary sparks presents noticeable faults at certain speeds and causes erratic performance of the internal combustion engine to which it is associated.

The main object of the invention is to improve the performance of an ignition system of the vibrator type.

A further object of the invention is to provide an ignition system of the vibrator type having improved ignition timing. conditions.

Another object of the invention is to provide an ignition system of the vibrator type having improved starting under all weather conditions.

Another object of the invention is to provide an ignition system wherein the operation of a vibrator is controlled to prevent the vibrator to cause the first ignition.

A more specific object of the invention is to provide a pilot relay to control the ignition such that the first spark will be produced by the breaker points upon opening of the latter.

The foregoing and other important objects of the present invention will become more apparent during the following dis closure and by referring to the drawings, in which:

FIG. I is a diagrammatic electric circuit of an ignition system in accordance with -a first embodiment of the invention;

FIG. 2 is a view of part'of FIG. 1, wherein the single pair of contacts is replaced by two pairs of contacts;

FIG. 3 is a view similar to FIG. 2 wherein there are three pairs of contacts;

FIG. 4 is a view similar to FIG. 3 showing a circuit wherein a vibrator is adapted to produce two sparks per cycle of vibration',

FIG. 5 is an electrical circuit diagram of an ignition system in accordance with a second embodiment of the invention adapted to be used with a magnetic flywheel;

FIG. 6 is an electrical circuit diagram of a third embodiment of the invention.

In the drawings, like reference characters indicate like elements throughout.

In FIG. 1, there is shown an ignition system for internal combustion engines, which comprises the usual storage battery 1 having its negative terminal grounded. An ignition switch 2 is connected at the positive terminal of the battery I. The primary winding 3 of an induction coil is connected to the switch 2 in series with the latter and with the battery I. A secondary winding 4 is disposed adjacent to said primary winding 3 and in cooperation therewith, as is well'known in the art. The secondary winding 4 is grounded at one end while the other end thereof is series connected to the distributor arm 5 of the distributor 6.

As is well known in the art, each fixed contact of the dis tributor 6 is connectcdto a corresponding spark plug. For the sake of clarity, only one spark plug 7 is illustrated. A timing switch is also provided and is represented in the diagrams of FIGS. 1, 5, and 6 by the breaker switch 8 comprising essentially a movable circuit breaker arm 9 and a fixed breaker point It). The aforementioned elements I to 10 inclusive are well known and need no further definition herein.

The ignition system, subject of the present invention, more particularly comprises the electrical circuits which are d located under the line 11 in FIGS. 1, 5, and 6.

Referring particularly to FIG. 1, a diode I2 is connected between the primary winding 3 and the breaker switch 8, in series with the battery I, the ignition switch 2, the primary winding 3 and the breaker switch 8. A vibratorcoil 13 is connected, through a wire B4, to the junction between the ignition switch 2 and the primary winding 3. An armature core 15 is axially positioned and fixedly retained within the vibrator coil 13 in order to determine an electromagnet.

A vibrator reed 16 has one end fixed and grounded while the other end thereof is resiliently movable adjacent and in close cooperation with one end of the armature core 15. A pair of contacts 17 and 18 are carried by the vibrator reed to to be alternatively moved between contacting and noncontacting engagement with fixed contacts 19 and 20 respectively. Fixed contact 19 is connected in series with coil 3 and wire 14, while fixed contact 20 is connected to ground through a capacitor 21. A diode 22 and pilot relay contacts 23 are connected in series between the capacitor 21 and the junction of the primary winding 3 with the diode 12. The pilot relay contacts 23, asshown in FIG. I, comprise a single pair of contacts 24 and 25. contact 25 is movable between a contacting position, shown in FIG. I, and a noncontacting position by means of a pilot relay coil 26 to be described in detail hereinafter.

The pilot relay coil 26 is connectedin series with a pilot diode 27 between wire I4 and the rotating arm 9 of the breaker switch 8. An armature core 28 is disposed axially within the pilot relay coil 26. A resistor 23 and a regulating diode 30 are connected in series in shunt with pilot relay coil 26. A pilot lamp 31 and a diode 32 are connected in series between wire 14 and the movable contact 25 of the pilot relay contacts 23. A resistor 33 is shunting the vibrator coil 13.

Before passing to the description of the other embodiment of the inventioma description of the operation of the embodiment heretofore described is presented. When the breaker switch 8 is closed, as in FIG. I, the closing of the ignition switch 2 will allow current to flow from the battery l, through the switch 2, the primary 3, the diode 12?. and the closed breaker switch 8, to ground. At the same time, the pilot relay coil 26 will be energized, causing the attraction ofthe movable contact 25 towards the magnetized armature core 23 and opening of the pilot relay contacts 23.

Through the normally closed contacts 17 and 19. current flows through the vibrator coil 13 and causes displacement of the oscillating reed 16; resulting in the opening of contacts 17 and 19 and closing of contacts 18 and 20.

When contacts 17 and 19 open, the vibrator coil 13 is.

deenergized and reed 16 'returns to its position where it reestablishes the engagement of contacts I7 and 19. This cycle of reed 16 repeats itself continuously due to the autoexcitation of the vibrator. When the breaker switch 8 is closed, the pilot relay contacts 23 are opened, causing interruption of the circuit between the contacts 18 and 20 and the primary winding 3. It is thus seen that, in the closed position of the breaker switch 8, the repeated openings and closings of contacts 18 and 20 do not induce any pulse in the primary winding 3.

When the breaker switch opens, a first spark is produced at one of thespark plugs 7. The pilot relay coil 26 being no further energized the movable contact is freed and the pilot relay contacts 23 close to establish the circuit between the pulses producing contacts 18 and 20 and the primary winding 3. At that moment, the vibrator continues its autoexcitation and pulses are produced by the contacts lb and 2t) and are transmitted to the primary winding 3.

Referring now to FIG. 2 it will be seen that the pilot relay contacts 23 may comprise two pairs of contacts instead ofonly one, as in FIG. 1.

A second pair of contacts 34 and 35 are mounted parallel to the first pair of contacts 24 and 25. Contact 34 is movable and adapted to be depressed downwardly by means of the stud 36 of electrically insulating material. The contact 35 is fixed and grounded. It is to be noted that the contacts 34 and 35 are connected in series with the pilot lamp 231 and they replace the diode 32 of FIG. 1.

When the ignition circuit of FIG. 1 is modified, as shown FIG 2, the operation is the same as herein before described except as for the function ofthe diode 32. In FIG. l, the diode 32 was used to amplify the amplitude of the pulses produced and transmitted to the primary winding 3. The second pair of contacts 34 and 35 control the operation of the pilot lamp 3i and hence, replaces the diode 32 used in the embodiment of FIG. 1. In the latter figure, the control circuit for the pilot lamp Si is connected to the auxiliary ignition circuit, thereby requiring diode 32 to prevent closing of the primary winding fi-through the vibrator l3, contacts 19 and 17 and the grounded vibrating reed 16.

FIG. 3 illustrates pilot relay contacts 23 generally similar to the pilot relay contacts 23 of FIG. I. in FIG. 3, a third pair of contacts 37 and 38 are provided in addition to the two pairs illustrated in FIG. 2;.Said contacts 3?, 33 are used to replace the diode l2. shown in the embodiment of FIG. ll.

FIG. 4} illustrates a different vibrator circuit arrangement for the contacts IVY-20, whereby to produce double sparking. The fixed contact 19 is grounded through a capacitor 39 and a wire dd interconnects the two fixed contacts 19 and 20.

FIG. is a circuit diagram of an ignition system according to the invention, particularly adapted to be used in conjunction with a magnetic flywheel or alternator. The latter being a conventional element, it is not shown in the drawings. The magnetic flywheel or alternator is operatively associated with a light winding 41 to produce pulsating current transmitted through wire 1 to the vibrator coil 13 to produce energization thereof and oscillation of the reed 16, resulting in openings and closing of contacts ill; and 20.

A full wave rectifier diode bridge 42 interconnects wire 14 and the breaker switch 8. The diode bridge 42 comprises four diodes 4-3-46 arranged in pairs determining two parallel branches wherein the diodes of one pair in one branch have their cathodes interconnected, while the diodes of the other pair in the other branch have their anode interconnected. The positive half wave passes through diode 43 and through wire 47, is fed to the pilot relay coil 26 and through wire 48, diode 44- and wire 49, to the breaker switch 8. Similarly, the negative half wave in wire 14 is fed through diode 45 and wire 48 to pilot relay coil 26 and from there, through wire 47, diode do and wire 49 to breaker switch 8.

It can readily be appreciated that a full wave rectified current is fed through pilot relay coil 2.6 and to breaker switchti. Therefore, when the latter is closed, the relay is energized and so are the contacts 37 and 38, while contacts 24-25 and 34- 35 are maintained open. In the closed position of the breaker switch 8, the primary winding 3 is placed in series with close contacts 37 and 38 and wire 49 causing a dc. voltage to be impressed on the breaker switch 8. When the breaker switch 8 is closed, the circuit between the vibrator contacts 18 and 20 and the primary winding 3 is interrupted by the open contacts 24 and 25 and the opening and closing of contacts 18 and 20 do not induce any pulsation in the primary winding 3. On the other hand, when breaker switch 8 opens, a pulsation goes through the primary winding 3 and induces a corresponding pulsation in the secondary winding 4, causing a first spark caused to be produced followed by a series of smaller sparks caused by repeated opening and closing of the contacts 18 and 20. When the breaker switch 8 closes, the pilot relay deenergizes, causing opening of contacts 3738 and closing of contacts 24-435 and 3435. When contacts 24 and 25 are closed, the pulses produced by the contacts 18 and 20 are transmitted to the primary winding 3, causing said series of smaller sparks.

FIG. 6, as FIG. 5, also shows a circuit diagram of an ignition system particularly adapted to be used in conjunction with a magnetic flywheel or alternator. in the embodiment of FIG. 6, the full wave rectification is done at the winding 41, such that dc. current is fed to wire M. in such a case, the full wave rectifier diode bridge 42 is dispensed with. In FIG. 6, the opposite ends of the winding 42 are connected to the anodes ofa pair of corresponding diodes 50 and 51 respectively. The cathodes of the rectifying diodes 50 and 551i are connected together and to wire 14. A grounded center tap 52 is associated with the winding 43.. The full wavc rectified current produced by the diodes 5t and 5t goes through wire 14-, vibrator coil 13, diode 53 and contacts 17 and 19 to ground. This energizes the vibrator and causes the reed 16 to move such to close contacts 18 and 24) and to open contacts 17 and l9.

The generator contained in the magnetic flywheel feeds the primary winding 3 through normally resting contacts 25, only when the breaker switch 8 is opened and the first sp rl-r. flashes upon closing of the latter. At that moment, the piiot relay closes contacts 38, 37, allowing flow of current to the primary winding 3 by means of the generator &3 through con tacts lit; and 20 of the vibrator to produce the auxiliary sparks during all the time the magnotogencrator is short-circuitcd by the breaker switch.

In the embodiments of H65. 5 and 6, the spark at the spark plug is obtained by suppression of a magnetic flux in a winding. Whether said winding is incorporated to the flywheel itseit' (F101. 5) or separate therefrom (FlG. d), the circuit diagram may be quite different specially when the suppression of the spark generating magnetic flux is obtained by interruption 0:

the primary current (FIG. 5), or by short circniting, closing the breaker (FIG. 6).

lclaim:

l. A control circuit for an internal combustion engine tion system having a voltage source, a primary winding and breaker contact, said control circuit comprising a circuit adapted to be connected in series with said primary wind c and including a pair of vibrator contacts adapted to be o en and closed by a vibrator operatively associated to said pai oi vibrator contacts, a relay switch connected in series between said primary winding and said pair of vibrator contacts er pilot relay connected to said breaker contacts and. adapted. to selectively open or close said relay switch in response :0 the closed and open positions respectively of the breaker contacts.

2. A control circuit for an ignition system as claimed in claim 1, wherein the pilot relay comprises a pilot relay coil connected in series with the voltage source and the breaker contacts, whereby when the latter are opened, the pilot relay is deenergized and the relay contacts are closed, and when the breaker contacts are closed the pilot relay is energized and the relay contacts are opened.

3. A control circuit for an ignition systemv as claimed in claim 2, whereinsaid vibrator comprises a vibrator coil connected in series with the voltage source and a vibrator reed and said pair of vibrator contacts comprise a fixed contact connected in series with the relay switch and a movable contact attached to said reed for bodily movement therewith.

4. A control circuit for an ignition system as claimed. in claim 3, wherein a first diode is connected in series with said pair of vibrator contacts, the relay switch and the prima j winding, said first diode being connected between said pair oi vibrator contacts and said primary winding.

5. A control circuit for an ignition system as claimed in claim 4, wherein the said voltage source, an ignition switch, said primary winding, a second diode and the breaker contacts are all connected in series, the voltage source is a battery and the second diode is connected to conduct in the direction from the battery to the breaker contacts.

6. A control circuit for an ignition system as claimed in claim 4, wherein the relay switch comprises a first and a second pair of relay contacts, the first pair of relay contacts being connected in series between the primary winding and the pair of vibrator contacts, and the second pair of relay con tacts being connected in series with a pilot lamp. parallcl to the vibrator coil.

7. A control circuit for an ignition system as claimed in claim 6, wherein the relay switch comprises a third pair of relay contacts connected in series between the cathode of first diode and the breaker contacts.

8. A control circuit for an ignition system as claimed in claim 3, wherein the voltage source produces alternating current, a full wave rectifier is interposed between the vol source and the pilot relay coil and the breaker contacts are connected in series with said pilot relay coil.

9. A control circuit for an 'tion system as claimed claim 8, wherein said full wave rectifier is a diode bridge having an output connected to said breaker contacts.

10. A control circuit for an ignition system as claimed in claim 9, wherein said full wave rectifier comprises a pair of diodes connected at the opposite ends of a secondary winding 

